Safety lock for oil burners



April 24, 1962 D. E. SCHOTT SAFETY LOCK FOR OIL BURNERS 5 Sheets-Sheet lFiled Feb. 16, 1960 a BY April 24, 1962 D. E. SCHOTT 3,031,210

SAFETY LOCK FOR OIL BURNERS Filed Feb. 16, 1960 5 Sheets-Sheet 2 FIG.3

INVENTOR.

BYJQJ/ 5 5M i: am 4 14: 1 4.

April 24, 1962 D. E. SCHOTT SAFETY LOOK FOR OIL BURNERS 5 Sheets-Sheet 5Filed Feb. 16, 1960 INVENTOR. M4 275M April 24, 1962 D. E. SCHOTT SAFETYLOCK FOR OIL BURNERS 5 Sheets-Sheet 4 Filed Feb. 16, 1960 Khw/ gm; 64AM;1%;4

April 24, 1962 D. E. SCHOTT SAFETY LOCK FOR OIL BURNERS 5 Sheets-Sheet 5Filed Feb. 16, 1960 FIG."

INVE TOR. wad 2% 3&3 l ,2 l d Patented Apr. 24., l 962 This inventionrelates to safety lock devices constructed to prevent the manualbreaking of a fluid line while the valve, through which liuid issupplied to the line, is open. More particularly, the invention isconcerned with a novel safety lock device which is especially adaptedfor use with an oil burner of the type commonly employed in marineboiler furnaces and acts to prevent the pulling of the burner from thefurnace, not only while the oil supply valve is open but also as long asthere is oil under pressure in the burner.

Oil-fired marine boiler furnaces are provided with a plurality ofburners, all of which are used only when the vessel is to be driven atthe highest possible speed, as in emergency. Under operating conditionsrequiring less than all the burners, those not in use must be pulledfrom the furnace to prevent their nozzles from being clogged withcarbon. In naval vessels, the pulling of oil burners may be of frequentoccurrence and, since burners are supplied with oil at pressures rangingfrom 250 F.

to 300 F. and at pressures as high'as 300 p.s.i., it isv necessary toprovide such a burner with a safety lock which prevents the pulling ofthe burner while the fuel valve is open. Even though the valve may beclosed, the burner may contain oil under residual pressure and thedevice should prevent pulling of the burner until such pressure hasdissipated.

The present invention is directed to the provision of an oil burnersafety locicwhich prevents pulling of a burner while the valve is openand while there is oil under pressurain the burner. The new lock alsoprevents accidental opening of the valve, when the burner is not inplace.

For a better understanding of the invention, reference may be made tothe accompanying drawings, in which FIG. 1 is an exploded longitudinalhorizontal sectional view with parts shown in plan, of one form of thenew lock and parts of the valve with which it is used;

PEG. 2 is a fragmentary view in side elevation with parts shown insection and broken away of a burner held in place by the new lock;

MG. 3 is a horizontal sectional view of the burner valve of FIG. 1equipped with the new safety lock and with its parts shown in operativecondition;

FlG. 4 is an elevational view of an interlock arm employed in the safetylock of the invention;

FIG. 5 is a sectional view on the lined-5 of FIG. 3;

P16. 6 is a view similar to FIG. 3 with the safety lock shown ininoperative condition;

FIG. 7 is an exploded view, partly in horizontal longitudinal sectionand partly in plan, of a form of the safety device employed with anotherform of fuel valve;

H63. 8 and 9 are end views of a valve handle and a ratchet;

FIG. 10 is a vertical longitudinal view showing a burner held in placeby the safety lock of FIG. 7;

FIG. 11 is a fragmentary horizontal sectional view through the oil valveof FIG. 10; and

FIG. 12 is a fragmentary sectional view on the line 12-12 of FIG. 11.

The safety lock and valve in the form shown in FIGS. l-6, incl.,comprise a housing 20 with an externally threaded inlet 21 having apassage 22 surrounded at its.

inner end by a seat. Flow through the valve is controlled by a valvemember comprising a head 23 engageable with the seat and mounted on astem Mthreaded in a bonnet 25 which forms part of the housing and isheld in place in one end of the housing by a bonnet nut 26. The valvehousing has an integral outlet extension Zila containing an outletpassage 27 surrounded at its outer end by a seat 28 formed with acircumferential recess, in which a gasket '29 is disposed.

A cylindrical body 31%) forming part of the housing is threaded on thebonnet 2s and has an car 31 extending laterally therefrom. Outwardlybeyond the threaded portion, the body is cylindrical and is providedwith diametrically disposed aXial slots 32;. At its outer end, thebonnet is of substantially larger diameter than the stem 2 passingtherethrough to form a chamber 33, which contains a sealing ring 34 andan annular piston sleeve 35,

, the ring and piston surrounding the stem.

I An interlock arm 36 has a ring 3 7 at one end, which encircles thebody Sill. At its outer side, the ring is formed with an internal flange38 formed with diametrical radial notches 33 A key 3% includes a ringdtl, which encircles the body and is provided with diametricallydisposed lugs dda, axial arms 41 lying aligned with and inward from thelugs, and radial ears 42 extending inward from the arms. The arms andtheears lie within the slots in the body and the ears terminate in front ofthe piston sleeve 35. At their outer ends, the arms 41 are formed withlongitudinal slots and a pair of pawls 4- are pivotally mounted in theslots. A washer 45 surrounds the arms dll inward from the pawls id andthe washer has internal ears ida extending into the slots 43 of the armsand a second washer as surrounds the arms and lies against the outerface of the ring 37 of the interlock arm 36. A coil spring 47 encirclesthe arms and bears at its ends against the washers 4-5, 46. A cover 48is seated at one end on a circumferential shoulder on washer 46 andextends outwardiy to engage the outer surface of the slotted cylindricalsection of the body ill The cover is held in place by a spiral lock ring4? seated in a groove in the outer surface of the body.

A tubular ratchet 5t} having an enlarged section with external axialratchet splines 51 surrounds the stem 24 with the "splines lying inposition to be engaged by the the other, against a washer 54 seated onthe inner end of the enlarged section of the ratchet.

The section 52 of the ratchet is internally slotted at 55 to receive theends of a key 56 mounted in an opening through the stem 2 and thesplined section of the ratchet is formed with spaced internal lugs 57having cam surfaces 57a lying at an angle to the axis of the stem. Ahandle 5% is mounted loosely on the stem and is held in place by awasher d? and a nut 68'. The handle is formed with a split hub 61, eachsection of which is receivable between the internal lugs on the ratchetand has an in clinedv cam surface 62 engageable with a cam surface 57aon the ratchet Ell.

The valve housing 2@ is formed with bosses 63 extending outwardly fromopposite sides of the outlet passage 27 and a yoke 64 is pivotallymounted on the ends of the bosses by bolts 65 extending through openingsin the arms of the yoke and threaded into the bosses 63. The head of oneof the bolts lies in position to be engaged by the arm 31 on the body 12and prevents the body from being turned off the bonnet. At its outerend, the yoke is provided with a bloss 64a, through which a bolt 66 isthreaded, and the bolt is provided with a conical end and an outersection formed with an inner series of short ratchet splines 67 facingin one direction and a second series of long ratchet splines 68 facingin the opposite cannot be turned to loosen the bolt.

direction. A handle 69 is mounted loosely on the'end section of the boltand is held in place by a washer 7t and a snap ring 71. Inward from thewasher, the hub of the handle is hollowed out to form a cavity 72, intowhich project pawls 73, 74 mounted in recesses in the walls of thecavity and pointing in opposite-directions. The pawls are acted on by aspring 75 tending to urge their ends into contact with the surface of.the section of the bolt provided with the ratchet splines.

At its free end, the interlock arm 36 carries a fork 76, the legs ofwhich are provided with internal cam surfaces 760. When the arm is swungto the horizontal position shown in FIG. 3, the legs of the fork extendupwardly on either side of the boss 64a on the yoke and lie between theyoke and the inner end of the hub on the handle 69. In this position ofthe handle, the pawls 73, 74 make contact with the long splines 68 onlyand, when the handle is turned clockwise as shown in FIG. 5, the pawl 74can engage a spline and turn the bolt to tighten it. When the interlockarm is swung downward, the handle can be moved inward along the bolt toplace the pawls in operative relation to the short splines 67 and, whenthe handle is turned counterclockwise, the pawl 73 co-operates with ashort spline 67 to loosen the bolt.

The burner comprises a pipe 77 having its outer end threaded into oneend of a U-shaped inlet fitting 78, the other end of which is adapted toengage the seat 28 surrounding the outlet passage 27 through the valvehousing. The fitting is provided with a conical socket 79 in line withthe end of the fitting engageable with the seat and adapted to receivethe conical end of the bolt 66. When the pipe 77 of the burner is inoperative position, it extends through a collar 86 attached to the valvehousing 20 and through a barrel 81 mounted in an opening in the outerfront wall 82 of the furnace.

Prior to the insertion of the burner, the head 23 of the .fuel valve hasbeen seated to close the inlet passage 22 by rotating the stem 24 bymeans of the handle 53. The rotation of the handle is transmitted to thestem through the'cam surfaces 62 on the hub of the handle and the camsurfaces 57a on the ratchet 50. When the head 23 is seated at the end ofthe inlet passage, further rotation of the handle causes the surfaces 62and 57a to force the ratchet inwardly along the stem. In such movement,the spring 53 is compressed and moves the key inward along the stem, sothat its lugs 40a pass out of the notches 38a on the internal flange ofthe interlock arm ring. While the pressure is thus applied to the keythrough the spring 53, the interlock arm can be swung to verticalposition to place its notches 38a out of alignment with the lugs 40a onthe key and, when the handle is released, the

spring 53 expands and forces the ratchet outwardly, at the same timerotating the handle slightly. Upon expansion of the spring 53, thespring 47, which is weaker than spring 53 and has been compressed duringthe compression of spring 53, is free to expand and its acts through thewasher 45 to move the key outwardly until its lugs 40a strike thesurface of the flange 38 on the interlock arm ring. The spring 47 alsoacts through the washer 45 to hold the pawls 44 in operative positionwith their ends between the splines 51 on ratchet 50 and preventingrotation of the ratchet and stem 24 in a direction to open the valve.Accordingly, when the interlock arm is in the vertical position, the keylugs 40a cannot enter the arm ring notches 38a, the pawls 44 lock theratchet 50 against rotation, and the handle 58, which is loose on thestem 24, cannot rotate the stem to open the valve, because the stem iskeyed to the immovable ratchet 50.

When it is desired to open the valve to supply oil to the burner, theinterlock arm 36 must be raised until the legs of its forked end liebetween the bolt handle 69 and the boss'64a at the outer end of theyoke, so that the handle cannot be moved to engage the short splines andthus The movement of the interlock arm to horizontal position aligns itsnotches 38a with the lug Stla on the key and, as soon as this occurs,the spring 47 moves the key outwardly along the stem with the lugsentering the notches. In such movement of the key, the tails of thepawls 44 strike the inner surface of the end of the cover, which acts asan abutment and causes the pawls to swing so that their ends aredisengaged from the splines 51 on the ratchet 50. The outward movementof the key thus disables the stemlocning means by rendering the pawlsinoperative and the position of the key, when the pawls are clear of thesplines, may, for convenience, be referred to as the disabling positionof the key. With the locking means disabled, the handle 53 can berotated to turn the ratchet and the stem 24 to open the valve.

When the burner is to be pulled, the interlock arm must be swung tovertical position to permit the bolt handle 69 to be moved inward toengage the short splines 67 on the bolt. The arm can be thus moved onlywhen the valve handle 58 has been rotated to seat the head 23 of thevalve to close the inlet passage and the handle has been further rotatedto compress the spring 53 to move the key 40 along the stem to free thekey lugs 46:: from the notches 33a in the arm ring. In such rotation ofthe handle, the spring 53 is acting to move the key against theresistance of the spring 47. If there is oil under pressure in the valvehousing beyond the valve head 23, as, for example, because the head hasnot been seated tightly or the valve leaks, the oil will flow along thestem and enter the chamber 33 to act on the sealing ring 34 and thepiston sleeve 35. The pressure of the sleeve on the cars 42 on the keyopposes the movement of the key by the spring 53 and, when theresistance of the spring 47 and the pressure of the oil acting throughthe piston sleeve 35 are suflicient to overcome the force of spring 53,the movement of the handle 58 to compress the spring 53 and release thekey lugs from the notches in the interlock arm will be ineffective forthe purpose. As a result, it will be impossible to swing the arm toinoperative vertical position until the oil pressure acting through thepiston sleeve has been dissipated. Accordingly, the new safety lockprevents the burner bolt from being loosened to permit pulling of theburner until the fuel valve is closed and thereis no substantialpressure at the outlet side of the valve.

A modified form of valve equipped with the new safety lock isillustrated in FIG. 7 as including a housing 90, in one end of which isreceived an inlet fitting 91 held in place by a nut 92 and containing aninlet passage 91a surrounded at its inner end by a seat. The housing hasintegral sections 96a and 9912 serving the purposes of the bonnet 25 andbody 30, respectively, and the section 9611 has an internally threadedpassage 93 receiving the threaded stem 94 of a valve member having ahead 95 which can be engaged with the seat on the end of the fitting toshut ofl flow through the valve. Near its end, the passage 93 isenlarged to form a chamber in which are disposed a sealing ring 96 and apiston sleeve 97 encircling stem 94. The section 90b of the housing hasa cylindrical end portion formed with diametrical longitudinal slots90c.

The ring 98 of an interlock arm 99 is rotatably mounted on section 96band has a radial slotted extension 100. A key 161 similar to key 40 ismounted within the ring of the interlock arm on the section 90b of thevalve housing and it is formed with axial lugs 101a, arms 102 alignedwith the lugs and extending axially from the ring, and internal radialears 103, the arms and the ears lying within the slots 900. The ends ofthe arms 102 are slotted and pawls 104 are pivotally mounted in theslots. A washer 105 encircles the arms and lies against the flanged endof the interlock arm ring 98 and a spring 106 corresponding to spring 47encircles the arms and bears at one end against the washer 105 and, atthe other, against the washer 107 which encircles the arms and lies incontact with the pawls 104. A ratchet 108 encircles the stern and has alarge diametrical section 109 having external ratchet splines 109a and asmall diameter section 110. A washer 111 encircles the section 110 ofthe ratchet and is engaged by one end of a spring 112 corresponding tothe spring 53 and bearing at its other end against the cars 1423 on thekey. The ratchet has an internal keyway for receiving a key 113 mountedin an opening through the stem 94 and is also provided with internallugs 114 with cam surfaces 114a corresponding to the lugs 57 with thesurfaces 57a.

A handle 115 is loosely mounted on the end of the stem and held in placeby a Washer 116 and aunt 117. The handle has a hub formed with spacedsections 118 corresponding to the hub section 61 on handle 58 and havingcam surfaces 118a corresponding to the sections 62 on sections 61.

The valve body has a projecting collar 119 open to the interior of thevalve body and a coupling member 120 extends into one end of the collarand is held in place by a coupling screw 121 threaded into the end ofthe coupling member through the other end oi the collar. The couplingmember is screwed on the lower threaded end of an inlet 122 on an outlethousing 123 which corresponds to the valve housing extension Zita andcontains a passage connected at one end to the inlet 122 and at itsother end having a bushing 125. I

A yoke 126 is pivotally mounted on the housing 123 and is formed at itsouter end with a boss 126a into which is threaded a bolt 127. The bolthas an outer section with short ratchet splines 128 for loosening thebolt and long ratchet splines 129 for tightening the bolt. A handle 13bis mounted on the end of the bolt and is provided with internal pawls131 corresponding to the pawls 73, 74.

A pin 132 is mounted in an opening in the housing 123 and a yoke 133which forms the second part of the interlock arm is mounted pivotally onthe pin. The yoke 13? is formed with spaced arms 134 corresponding tothe legs 76 on the interlock arm 36 and having cam surfaces 134acorresponding to the cam surfaces 76a. The yoke is formed with an arm135 having a roller 136 mounted on a pin in the arm and lying within theslot in the part 100 of the interlock arm.

The burner employed with the valve and lock of FIGS. 742, incl, includesa pipe 137 threaded to the end of a U-shaped fitting 138 containing apassage 139 surrounded at one end by a seat 1411. When the burner is inoperative position, it extends through the housing 123 and is held inplace with its seat 140 against the end of bushing 125' by the pressureof the bolt 127. When the burner is in use, the yoke 133 is in thehorizontal position with its arms 134 between the end of yoke 126 andthe hub of handle 139;. When the burner is to be pulled, the valve mustbe closed, after which the yoke 133 is swung down, the bolt is backedoil, and the yoke 126 is swung down. When the burner tube is removedfrom housing 123, the entrance to the housing is closed by a pivoteddoor 141.

The valve and safety lock shown in FIGS. 7-l0, incl, operate in the sameway as the first form of the valve and safety lock shown in FIG. 1. Whenthe valve has been closed to permit the pulling of the burner, the key101 has been moved in a direction toward the valve housing so that itslugs 101a are out of the notches 98a on the interlock arm ring 98.Thereafter, when the yoke 133 forming part of the interlock arm is swungfrom between the bolt yoke 126 and the handle 130, the notches 98a onthe interlock arm ring move out of alignment with the lugs on theinterlock arm ring. In this condition of the parts, the ends of thepawls 10 4 lie in the splines 109a on the ratchet 109 and hold theratchet against movement with the stem in the direction required tounseat the valve.

When the burner is reinserted in the furnace and secured in place by thebolt, the yoke 133 is swung into place between the bolt yoke 126 andthehandle 130 and this makes it impossible to loosen the bolt by thehandle. At the same time, the movement of the yoke 133 to horizontalposition aligns the notches 99a in the interlock arm ring with the lugs101a on the key and the spring 106 can then act to move the key in thedirection away from the valve housing with its lugs entering theinterlock arm ring notches. This movement of the key causes the pawls1104 to engage the cover and be swung thereby out of engagement with thesplines of ratchet 108. The handle 115 may then be turned to open thevalve.

When the burner is to be pulled, the bolt cannot be backed 011, untilthe yoke 133 has been swung to vertical position, and the yoke cannot beswung until the ears of the key have been moved out of the notches onthe interlock arm ring. Such movement of the key requires that the stem94 be turned to compress the spring 112 so that it overcomes the spring116 and moves the key toward the valve housing. The spring 112 is thuscompressed by movement of the ratchet 168 along the stem 94 and suchmovement of the ratchet requires that the valve member be seated andthat the stem be rotated additionally to cause the cam surfaces 118a onthe sections of hub 118 on the handle to co-operate with the camsurfaces 114a on the internal lugs of the ratchet to move the ratchetendwise. Any oil pressure in the valve will act through the gasket 96and the piston sleeve 97 to resist the movement of the key by the spring112. Accordingly, the yoke 13% cannot be swung to permit removal of theburner bolt until the valve has been closed and pressure on the outletside of the valve has been dissipated.

It will be apparent that, with both forms of the new safety lock, it isnot possible to pull the burner while the oil valve is open or to openthe valve accidentally when the burner is out of position. The reason isthat, in order to loosen the bolt, and remove the burner, it isnecessa1y to lower the interlock arm to permit the bolt handle to beengaged with the short splines on the bolt. However, when the valve isopen, the key lugs are engaged in the notches in the arm ring and thearm cannot be lowered. When the valve has been closed, oil pressure inthe burner has been dissipated, and the arm has been released from thekey and moved to vertical position, the valve cannot be opened until thearm has again been swung upward to permit the movement of the key, whichrees the pawls from the ratchet keyed to the stem. As

the upward swinging of the arm must be a deliberate action, accidentalopening of the valve with the burner out of position cannot occur.

I claim:

1. An oil burner safety lock, which comprises an oil valve having ahousing with an inlet and an outlet surrounded by a seat, and a stemmounted in the housing and movable in opposite directions to open andclose the valve, means, including engageable members mounted on thehousing and the stem, for locking the stem against valve-openingmovement, a key mounted on the housing and movable to and from aposition, in which it disables the locking means by preventingengagement of said members, a spring tending to move the key to itsdisabling position, a burner inlet fitting engageable with the seat toreceive oil through the housing outlet, a bolt engageable with thefitting and operable when tightened to hold the fitting on the seat, amounting for the bolt attached to the housing, separate means fortightening and loosening the bolt, an arm mounted on the housing andhaving parts engageable with parts of the key and of the bolt-looseningmeans, the arm being movable between a position, in which it holds thekey against movement to its disabling position, and a second position,in which it disables thebolt-loosening means and is held in place by thekey when the latter is in disabling position, means for moving the stem,means operable by the stem-moving means at the end of the valve-closingmovement of the stem to urge the key away from its disabling position,and means engageable with the key and operable by oil pressure at theoutlet side of the valve to resist movement of the key in a directionaway from its disabling position.

2. The oil burner safety lock of claim 1, in which the means for'lockingthe stem against valve opening movement include a ratchet encircling thestern and keyed thereto, the ratchet having external splines, and pawlsmounted on the key and engageable with the splines.

3. The oil burner safety lock of claim 1, in which the housing has acylindrical portion with longitudinal slots and the key is formed witharms entering and movable in the slots.

4. The oil burner safety lock of claim 1, in which the key is movableaxially of the stem, means on the housing guiding the key in itsmovement, and the arm includes a ring encircling the stem and rotatableto and from a position, in which parts on the ring engage parts on'thekey and hold the key against movement to disabling position.

5. The oil burner safety lock of claim 4, in which the arm ring has aninternal flange with notches and the key has a ring encircling the stemand having lugs movable into the arm ring notches by the spring actingon the key, when the arm ring is in one position, the lugs engaging thefiange, when the arm ring is in another position, and preventingmovement of the key by the spring.

6. The oil burner safety lock of claim 1, in which the means for movingthe stem includes a handle mounted on the stem and the means for urgingthe key to inoperative position includes a spring acting on the key andmeans operable by the handle to apply force through the spring to thekey.

7. The oil burner safety lock of claim 6, in which the key includes aring encircling the stem and having internal ears engaged by the springcompressible by the means operable by the handle and the means operableby oil pressure includes a piston sleeve encircling the stem andengaging the ears.

8. The oil burner safety lock of claim 6, in which the means for lockingthe stem against valve opening movement include a ratchet encircling andkeyed to the'stem and having external splines and pawls mounted on thekey and engageable with the splines, the spring which urges the key toinoperative positionbears at oneend on the ratchet, and the ratchet ismovable by the handle, when the valve is closed, to compress the spring.

9. The oil burner safety lock of claim 1, in which the means responsiveto oil pressure at the outlet side of the valve include a piston sleeveencircling the stem and acted on by oil in the valve housing, the sleevebeing engageable with the key.

10. The oil burner'safety lock of claim 1, in which the means fortightening and loosening the bolt include a handle movable along thebolt and having pawls extending in opposite directions and at least twosplines on the bolt engageable by respective pawls to rotate the bolt inopposite directions to loosen and tighten it, and the arm has meansoperative, when the arm has released the key for movement to disablingposition, to hold the handle with its pawls out of operative relation tothe bolt loosening spline.

11. The oil burner safety lock of claim 10, in which the arm has a forkmovable with the arm to a position straddling the bolt and preventingmovement of the bolt handle to place one of its pawls in operativeengagement with the bolt loosening spline.

12. The oil burner safety lock of claim 1, in which one end of thespring engages an immovable seat, the locking means include pawlspivoted on the key and engageable with a splined member keyed to thestem, and the spring acts at its other end on the pawls to swing theminto engagement with the splined member and to urge the key away fromthe seat.

13. The oil burner safety lock of claim 1, in which the arm is formed oftwo parts, one part of the arm including a ring encircling the stem andhaving a projecting lug, the second part of the arm including a pivotedmember, and a slot and pin connection between the parts of the arm forcausing them to swing in unison.

14. The oil burner safety lock of claim 1, in which the housing includesan internally threaded bonnet, a body formed with an axially slottedcylindrical portion, and an extension integral with the housing andhaving an outlet passage surrounded by an external seat, and the stemextends through the body and is threaded into the bonnet.

15. The oil burner safety lock of claim 14, in which the bonnet'and bodyare integral with the housing and the outlet extension is separate fromand connected to the housing.

References Iited in the file of this patent UNITED STATES PATENTS1,625,098 Rudolph Apr. 19, 1927 2,857,128 Stern Oct. 21, 1958 2,876,983Martensson et al. Mar. 10, 1959 2,919,145 McGraw et al Dec. 29, 1959

